>>54103244Considering they are not ‘Paradox’ Pokémon, but Ancient and Future Pokémon with a group descriptor of ‘the Paradox Pokemon’, that’s due to the fact their origin is brought into question. They are stated to be from the ancient past/far future, but evidence of their existence in the recent past mens its impossible for them to have been there. It’s a Paradox. I’m not arguing this point, or their classification as paradoxes, because this is simply what in-universe we know to be ‘true’ so far.
Out of universe, and in actuality, their existence can be explained if they are actually artificial lifeforms made to replicate their base Pokémon forms. A Demiurge, a being who believes itself to be ‘God’, but is in actuality just a sufficiently advanced being that has basic Omniscience, but lacks Omnipotence to match it and is hence ‘limited’ to being a ‘shaper’ of what it has at hand, means it cannot create ‘more’ or use more than what it has on-hand to work with, or else it would be an actual God.
So Terapagos, being a living DNA ‘ark’ of the Pokémon world, and having access to Pokémon genetics from A-Z, past to future, means it could then take a Jigglypuff, have an idea for how to make it ‘perfect’, and then turn it into Scream Tail as a result. When it’s given an ‘Imaginary’ Pokémon, it can’t just turn a dream into reality, so it takes Suicune or Virizion, and makes the closest thing to it.
It lacks imagination, it lacks the power to actually time travel. What it can do is ‘create’, in actuality just transform, Pokemon on hand into ‘new’ Forms.